Converted by Bishop Despencer in late C14.
Brick dress- ings to C14 work.
C14 work includes a semicircular tower base matching the original stair turret and several masonry partitions with brick dressings.
The site is surrounded by C14 earthworks.
S.E. Rigold "The Anglian Cathedral of North Elmham, Norfolk" Medieval Archaeology, VI- VII, 1962-3
The building is also a scheduled Ancient Monument.